external/bsd/lutok/dist/examples/interpreter.cpp

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  28
  29 /// \file examples/interpreter.cpp
  30 /// Implementation of a basic command-line Lua interpreter.
  31
  32 #include <cstdlib>
  33 #include <iostream>
  34 #include <string>
  35
  36 #include <lutok/exceptions.hpp>
  37 #include <lutok/operations.hpp>
  38 #include <lutok/state.ipp>
  39
  40
  41 /// Executes a Lua statement provided by the user with error checking.
  42 ///
  43 /// \param state The Lua state in which to process the statement.
  44 /// \param line The textual statement provided by the user.
  45 static void
  46 run_statement(lutok::state& state, const std::string& line)
  47 {
  48     try {
  49         // This utility function allows us to feed a given piece of Lua code to
  50         // the interpreter and process it.  The piece of code can include
  51         // multiple statements separated by a semicolon or by a newline
  52         // character.
  53         lutok::do_string(state, line);
  54     } catch (const lutok::error& error) {
  55         std::cerr << "ERROR: " << error.what() << '\n';
  56     }
  57 }
  58
  59
  60 /// Program's entry point.
  61 ///
  62 /// \return A system exit code.
  63 int
  64 main(void)
  65 {
  66     // Create a new session and load some standard libraries.
  67     lutok::state state;
  68     state.open_base();
  69     state.open_string();
  70     state.open_table();
  71
  72     for (;;) {
  73         std::cout << "lua> ";
  74         std::cout.flush();
  75
  76         std::string line;
  77         if (!std::getline(std::cin, line).good())
  78             break;
  79         run_statement(state, line);
  80     }
  81
  82     return EXIT_SUCCESS;
  83 }